The superconducting Bardeen–Cooper–Schrieffer (BCS) density of states (DOS) is characterised by a gap \(\Delta \)  around the Fermi energy which prevents quasiparticle excitations at energies below it. This picture changes in systems with spatially-inhomogeneous pairing potentials, such as weak links between two superconductors (SCs). In such cases, the DOS contains states inside the gap known generically as Andreev bound states (ABSs) [1]}. Excitations created by the addition or removal of a quasiparticle to/from ABSs have been observed in e.g. carbon nanotubes  [2]}, [3]}, superconducting atomic point contacts [4]}, graphene [5]} and hybrid semiconducting-superconducting systems based on nanowires (NWs) [6]}, [7]}, [8]}, [9]}, [10]}, [11]}, [12]}, [13]}, [14]}, [15]}.
While ABSs are interesting, not only as e.g. Andreev qubits [16]}, [17]}, but also for the rich physics they offer, the intense research activity of the last few years in the hybrid NW platform has arguably been motivated by the prediction that a topological SC state with Majorana zero modes (MZMs) can be engineered out of them [18]}, [19]} (see also Refs. [20]}, [21]} for recent reviews).
Despite the fact that several experiments in such platforms have reported on signatures compatible with MZMs [22]}, [23]}, [24]}, [25]}, [26]}, [27]}, the Majorana interpretation has been challenged since zero-energy ABSs, without an underlying topological state, can mimic MZMs [28]}, [29]}, [30]}, [31]}, [32]}, [33]}, [34]}, [35]}, [36]}, [34]}, [38]}, [39]}.
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